JP4115634B2 - Synchronous control device for multiple electromagnetic induction coils - Google Patents
Synchronous control device for multiple electromagnetic induction coils Download PDFInfo
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- JP4115634B2 JP4115634B2 JP21086899A JP21086899A JP4115634B2 JP 4115634 B2 JP4115634 B2 JP 4115634B2 JP 21086899 A JP21086899 A JP 21086899A JP 21086899 A JP21086899 A JP 21086899A JP 4115634 B2 JP4115634 B2 JP 4115634B2
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- Prior art keywords
- electromagnetic induction
- induction coils
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
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- General Induction Heating (AREA)
Description
【０００１】
【発明が属する技術分野】
本発明は、複数の隣接電磁誘導コイルの同期化制御装置に関し、更に詳細には複数の隣接配置した電磁誘導コイルを、相互干渉させることなく作動させることのできる複数の隣接電磁誘導コイルの同期化制御装置に関するものである。
【０００２】
【従来の技術】
圧延ロールの焼き入れの際の加熱に電磁誘導加熱が適用されることは、例えば実公平３−３９４８２号公報などによって周知である。この公報の記載によれば、昇温用加熱コイルと温度保持用加熱コイルとを近接させて配置し、同時に作動させる必要がある。
【０００３】
【発明が解決しようとする課題】
ところで、前記複数の電磁誘導コイルを接近させて同時に作動させると、高周波電流の周波数及び位相のずれによる干渉が起こるという問題がある。かかる相互干渉を防止する手段として、前記実公平３−３９４８２号公報に開示された手段は、図３に示すとおり、昇温用電磁誘導コイル１に出力変圧器２を接続した回路と、温度保持用電磁誘導コイル３に可変リアクトルからなる電流調整器４及び出力変圧器５を接続した回路とを、１台の周波数変換装置６に並列に接続し、前記電磁誘導コイル１，３のそれぞれとコンデンサ７とで決定される共振高周波によって電磁誘導加熱を行うようにしたものである（以下共振型という）。
【０００４】
上記電流調整器４の作用は、昇温用電磁誘導コイル１と温度保持用電磁誘導コイル３との間隔をより狭めることを可能にするものである。電流調整器４を設けない場合の電磁誘導コイル１と３とのコイル間隔の限界値（１５０〜２００mm）以下とすることが可能となり、電力消費を少なくし、しかも焼き入れ深度を深くすることができると説明している。なお、図３に示す符号８は電源用変圧器、９は電源スイッチをそれぞれ表す。
【０００５】
なお、前記周波数変換器６に図３に示す３相ダイオード全波整流器（ＲＥＣ）10、平滑用直流リアクトル（ＤＣＬ）11及びサイリスタインバータ12を適用して試験したところ、共振型の発振周波数は、電磁誘導コイル１，３のコイルインピーダンスとコンデンサ７の容量とによって決まるため、圧延ロールの加熱を行う場合には、コイル内にロールが進入するに伴い、前記コイルインピーダンスが大きく変動することによって発信周波数が変動し、電流値を一定に調整するだけでは所定の加熱温度に達することができないという問題がある。
【０００６】
本発明は、以上の問題に着目してなされたものであり、互いに近接配置する複数の電磁誘導コイルのコイルインピーダンスの変動に関係なく、電流を制御可能で、相互干渉のない複数の隣接電磁誘導コイルの同期化制御装置を提供することを目的としている。
【０００７】
【課題を解決するための手段】
以上の目的を達成するための本発明の複数の電磁誘導コイルの同期化制御装置は、複数の電磁誘導コイルにそれぞれ接続する複数のＰＷＭインバータと、該複数のＰＷＭインバータに基準波形信号を与える電流同期化信号装置とを備え、前記複数のＰＷＭインバータの出力電流の周波数及び位相を前記基準波形信号に同期させると共に、前記出力電流の電流レベルを前記基準波形信号に基づいて調整するものである。
【０００８】
前記ＰＷＭインバータは、周知のPulse-Width Modulation（パルス幅調節）インバータであり、本発明のＰＷＭインバータとして従来から使用されている基本回路及び変換素子、駆動回路などを適宜使用することができる。使用しうる変換素子としては、絶縁型バイポーラトランジスタ（ＩＧＢＴ）、ゲートターンオフ（ＧＴＯ）サイリスタ、トランジスタなどである。
【０００９】
【発明の実施の形態】
以下添付の図面を参照し、一実施の形態により本発明を具体的に説明する。
【００１０】
図１に示す第１の実施の形態による複数の電磁誘導コイルの同期化制御装置13は、圧延ロール（図示せず）の表面焼き入れに適用したものであり、昇温用電磁誘導コイル１及び温度保持用電磁誘導コイル３のそれぞれに電源用変圧器14及び15を用い、それぞれの電源を別系統とした。
【００１１】
そして、昇温用電磁誘導コイル１用インバータとして焼き入れ加熱用ＰＷＭインバータ16を取り付け、また温度保持用電磁誘導コイル３用インバータとして温度保持用ＰＷＭインバータ17を取り付け、電流同期化信号出力回路18の同期信号Ｓを、焼き入れ加熱用ＰＷＭインバータ16、温度保持用ＰＷＭインバータ17それぞれの制御端子に与えるように接続した。なお、図３で説明したものと同様の部材には同じ符号を付し説明を省略する。
【００１２】
以上説明した第１実施の形態による同期化制御装置13は、昇温用電磁誘導コイル１と温度保持用電磁誘導コイル３との間隔を接近させたにも関わらず相互干渉が起こらず、それぞれ独立した電力制御、コイルの周波数及び波形の制御が容易で、均一な加熱温度が得られた。しかも主回路構成が単純であり、信頼性の高い焼き入れ装置が得られた。
【００１３】
第２の実施の形態による複数の電磁誘導コイルの同期化制御装置 13-1 、 13-2 を示す図２においては、３相ダイオード全波整流器10-1，10-2は、いずれも商用３相交流電源Ｅ-1，Ｅ-2を使用した基本回路構成とし、ＰＷＭインバータ21-1，21-2は、いずれも素子に絶縁型バイポーラトランジスタＱ11，Ｑ12，Ｑ13，Ｑ14及びＱ21，Ｑ22，Ｑ23，Ｑ24による回路構成としたものであり、図１と同様の部材には同じ符号を付し説明を省略する。
【００１４】
インバータ21-1，21-2を駆動するディジタル制御回路22-1，22-2は、共通の基準信号波発生回路19から与えられる基準信号によって駆動されるものであり、それぞれ信号波作成回路23-1，23-2、三角波比較回路24-1，24-2及びゲートパルス発生回路25-1，25-2によって構成した。
【００１５】
信号波作成回路23-1，23-2から出力する信号波ｆ-1，ｆ-2の周波数及び位相は基準信号波Ｆに同期し、それぞれの電流レベルは、可変抵抗器からなるレベル設定器26-1，26-2及び電磁誘導コイル20-1を流れる電流Ｉ-1，電磁誘導コイル20-2を流れる電流Ｉ-2によって、それぞれ調整される。前記電流Ｉ-1，Ｉ-2は、変流器27-1，27-2（図２）によって検出し、信号波作成回路23-1，23-2にそれぞれフィードバックさせた。
【００１６】
そして作成した信号波ｆ-1，ｆ-2を、三角波比較回路24-1，24-2に与える。この三角波比較回路24-1，24-2におけるキャリア周波数は４ｋＨｚ（２５０マイクロ秒毎）とした。ゲートバルス発生回路25-1の出力信号ｓ11，ｓ12，ｓ13，ｓ14及びゲートバルス発生回路25-2の出力信号ｓ21，ｓ22，ｓ23，ｓ24を、それぞれ対応するＩＧＢＴＱ11，Ｑ12，Ｑ13，Ｑ14及びＱ21，Ｑ22，Ｑ23，Ｑ24におけるゲートｇ11，ｇ12，ｇ13，ｇ14及びｇ21，ｇ22，ｇ23，ｇ24にそれぞれ与えるようにした。
【００１８】
【発明の効果】
以上説明したように本発明の複数の電磁誘導コイルの同期化制御装置は、コイル毎に電源を別系統とし、それぞれに出力周波数及び波形をディジタル制御することができるＰＷＭインバータを使用したので、複数の電磁誘導コイルを互いに接近させて配置した場合でも、コイル間の相互干渉を無くし、各電磁誘導コイルを独立して電力制御、コイルの周波数及び波形を制御することが容易である。
【００１９】
したがって、誘導加熱による焼き入れなど、複数の電磁誘導コイルを接近させて配置する場合に、主回路構成が単純で、信頼性の高い装置として提供することができる。
【図面の簡単な説明】
【図１】 本発明の第１の実施の形態による複数の電磁誘導コイルの同期化制御装置の回路の概要説明図である。
【図２】 本発明の第２の実施の形態による複数の電磁誘導コイルの同期化制御装置の回路の説明図である。
【図３】 従来例によるサイリスタインバータを使用した共振型誘導加熱回路の概要説明図である。
【符号の説明】
１ 電磁誘導コイル
３ 電磁誘導コイル
５ 出力変圧器
16 ＰＷＭインバータ
17 ＰＷＭインバータ
18 電流同期化信号出力回路
19 基準信号波発生回路
20-1 電磁誘導コイル
20-2 電磁誘導コイル
21-1 ＰＷＭインバータ
21-2 ＰＷＭインバータ
23-1 信号波作成回路
23-2 信号波作成回路
26-1 レベル設定器
26-2 レベル設定器 [0001]
[Technical field to which the invention belongs]
The present invention relates to a synchronization control device for a plurality of adjacent electromagnetic induction coils, and more specifically, a synchronization of a plurality of adjacent electromagnetic induction coils capable of operating a plurality of adjacently arranged electromagnetic induction coils without causing mutual interference. The present invention relates to a control device.
[0002]
[Prior art]
For example, Japanese Utility Model Publication No. 3-39482 discloses that electromagnetic induction heating is applied to heating during quenching of a rolling roll. According to the description of this publication, it is necessary to arrange the heating coil for raising the temperature and the heating coil for maintaining the temperature close to each other and operate them simultaneously.
[0003]
[Problems to be solved by the invention]
By the way, when the plurality of electromagnetic induction coils are brought close to each other and operated at the same time, there is a problem that interference occurs due to a frequency and phase shift of the high-frequency current. As means for preventing such mutual interference, the means disclosed in the Japanese Utility Model Publication No. 3-39482, as shown in FIG. 3, includes a circuit in which the output transformer 2 is connected to the electromagnetic induction coil 1 for temperature rise, A circuit in which a current regulator 4 made of a variable reactor and an output transformer 5 are connected to the electromagnetic induction coil 3 for use, and connected in parallel to a single frequency converter 6, and each of the electromagnetic induction coils 1 and 3 and a capacitor The electromagnetic induction heating is performed by the resonance high frequency determined by the number 7 (hereinafter referred to as resonance type).
[0004]
The action of the current regulator 4 makes it possible to further narrow the interval between the temperature raising electromagnetic induction coil 1 and the temperature maintaining electromagnetic induction coil 3. When the current regulator 4 is not provided, the coil spacing between the electromagnetic induction coils 1 and 3 can be set to a limit value (150 to 200 mm) or less, thereby reducing power consumption and increasing the quenching depth. Explains that you can. In addition, the code | symbol 8 shown in FIG. 3 represents a power transformer, and 9 represents a power switch, respectively.
[0005]
When the frequency converter 6 was tested by applying the three-phase diode full-wave rectifier (REC) 10, the smoothing direct current reactor (DCL) 11 and the thyristor inverter 12 shown in FIG. since determined by the capacitance of the coil impedance and the capacitor 7 of the electromagnetic induction coils 1, 3, in the case of heating of the rolling rolls, transmission frequency by the roll in the coil due to advances, the coil impedance fluctuates greatly There is a problem that the predetermined heating temperature cannot be reached only by adjusting the current value to be constant.
[0006]
The present invention has been made paying attention to the above problems, and can control a current regardless of fluctuations in coil impedance of a plurality of electromagnetic induction coils arranged close to each other, and can control a plurality of adjacent electromagnetic inductions without mutual interference. An object of the present invention is to provide a coil synchronization control device.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a synchronization control apparatus for a plurality of electromagnetic induction coils according to the present invention includes a plurality of PWM inverters respectively connected to the plurality of electromagnetic induction coils, and a current that provides a reference waveform signal to the plurality of PWM inverters And a synchronizing signal device for synchronizing the frequency and phase of the output currents of the plurality of PWM inverters with the reference waveform signal and adjusting the current level of the output current based on the reference waveform signal .
[0008]
The PWM inverter is a well-known Pulse-Width Modulation (pulse width adjustment) inverter, and a basic circuit, a conversion element, a drive circuit, and the like conventionally used as the PWM inverter of the present invention can be appropriately used. Examples of conversion elements that can be used include an insulated bipolar transistor (IGBT), a gate turn-off (GTO) thyristor, and a transistor.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
[0010]
Synchronization control unit 13 of a plurality of electromagnetic induction coils of the first embodiment are shown in FIG. 1 is applied to a surface hardening of the rolling rolls (not shown), an electromagnetic induction coil 1 for heating and using the power supply transformer 14 and 15 to each of the temperature holding electromagnetic induction coil 3, and to that respective of another system power.
[0011]
Then, a quenching and heating PWM inverter 16 is attached as an inverter for the temperature raising electromagnetic induction coil 1, and a temperature holding PWM inverter 17 is attached as an inverter for the temperature holding electromagnetic induction coil 3 and the current synchronization signal output circuit 18 The synchronization signal S was connected to the control terminals of the quenching heating PWM inverter 16 and the temperature holding PWM inverter 17. In addition, the same code | symbol is attached | subjected to the member similar to what was demonstrated in FIG. 3, and description is abbreviate | omitted.
[0012]
The synchronization control device 13 according to the first embodiment described above does not cause mutual interference even when the distance between the temperature-increasing electromagnetic induction coil 1 and the temperature maintaining electromagnetic induction coil 3 is close, and each is independent. The power control, the coil frequency and the waveform were easily controlled, and a uniform heating temperature was obtained. In addition, a quenching apparatus having a simple main circuit configuration and high reliability was obtained.
[0013]
In FIG. 2 showing a plurality of electromagnetic induction coil synchronization control devices 13-1 and 13-2 according to the second embodiment, the three- phase diode full-wave rectifiers 10-1 and 10-2 are both commercial 3 The basic circuit configuration uses phase AC power supplies E-1 and E-2. The PWM inverters 21-1 and 21-2 are all insulated bipolar transistors Q 11, Q 12, Q 13, Q 14 and Q 21, Q 22, Q 23. , Q24, and the same components as those in FIG.
[0014]
The digital control circuits 22-1 and 22-2 for driving the inverters 21-1 and 21-2 are driven by the reference signal supplied from the common reference signal wave generating circuit 19, and each of them is a signal wave generating circuit 23. -1,23-2, triangular wave comparison circuits 24-1 and 24-2, and gate pulse generation circuits 25-1 and 25-2.
[0015]
The frequency and phase of the signal waves f-1 and f-2 output from the signal wave generating circuits 23-1, 23-2 are synchronized with the reference signal wave F, and each current level is a level setting device including a variable resistor. 26-1 and 26-2, the current I-1 flowing through the electromagnetic induction coil 20-1, and the current I-2 flowing through the electromagnetic induction coil 20-2 are adjusted respectively. The currents I-1 and I-2 were detected by current transformers 27-1 and 27-2 (FIG. 2) and fed back to signal wave generating circuits 23-1 and 23-2, respectively.
[0016]
Then, the generated signal waves f-1 and f-2 are given to the triangular wave comparison circuits 24-1 and 24-2. The carrier frequency in the triangular wave comparison circuits 24-1 and 24-2 was 4 kHz (every 250 microseconds ). The output signals s11, s12, s13, and s14 of the gate pulse generator circuit 25-1 and the output signals s21, s22, s23, and s24 of the gate pulse generator circuit 25-2 are respectively converted into the corresponding IGBTs Q11, Q12, Q13, Q14, and Q21. , Q22, Q23, and Q24 , gates g11, g12, g13, and g14 and g21, g22, g23, and g24, respectively .
[0018]
【The invention's effect】
As described above, the synchronization control device for a plurality of electromagnetic induction coils according to the present invention uses a PWM inverter capable of digitally controlling the output frequency and waveform for each coil, using a separate power source for each coil. Even when the electromagnetic induction coils are arranged close to each other, mutual interference between the coils is eliminated, and it is easy to control the power control and the coil frequency and waveform independently for each electromagnetic induction coil.
[0019]
Therefore, when a plurality of electromagnetic induction coils are arranged close to each other, such as quenching by induction heating, the main circuit configuration is simple and can be provided as a highly reliable device.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory diagram of a circuit of a synchronization control device for a plurality of electromagnetic induction coils according to a first embodiment of the present invention.
FIG. 2 is an explanatory diagram of a circuit of a synchronization control device for a plurality of electromagnetic induction coils according to a second embodiment of the present invention.
FIG. 3 is a schematic explanatory diagram of a resonance type induction heating circuit using a thyristor inverter according to a conventional example.
[Explanation of symbols]
1 Electromagnetic induction coil
3 Electromagnetic induction coil
5 Output transformer
16 PWM inverter
17 PWM inverter
18 Current synchronization signal output circuit
19 Reference signal wave generator
20-1 Electromagnetic induction coil
20-2 Electromagnetic induction coil
21-1 PWM inverter
21-2 PWM inverter
23-1 Signal wave generation circuit
23-2 Signal wave generation circuit
26-1 Level setter
26-2 Level setter
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21086899A JP4115634B2 (en) | 1999-07-26 | 1999-07-26 | Synchronous control device for multiple electromagnetic induction coils |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21086899A JP4115634B2 (en) | 1999-07-26 | 1999-07-26 | Synchronous control device for multiple electromagnetic induction coils |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2001035645A JP2001035645A (en) | 2001-02-09 |
| JP4115634B2 true JP4115634B2 (en) | 2008-07-09 |
Family
ID=16596442
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21086899A Expired - Fee Related JP4115634B2 (en) | 1999-07-26 | 1999-07-26 | Synchronous control device for multiple electromagnetic induction coils |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4115634B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100750546B1 (en) * | 2002-06-26 | 2007-08-20 | 미쯔이 죠센 가부시키가이샤 | Induction heating method and apparatus |
| KR100795737B1 (en) * | 2007-01-24 | 2008-01-17 | 미쯔이 죠센 가부시키가이샤 | Induction heating method and apparatus |
| JP2008243546A (en) * | 2007-03-27 | 2008-10-09 | Mitsui Eng & Shipbuild Co Ltd | Induction heating device |
| CN110139412B (en) * | 2019-06-20 | 2024-11-05 | 胜利油田金色河口石化工程有限公司 | Electromagnetic induction heating device |
| EP3790180B1 (en) * | 2019-09-04 | 2022-08-10 | IAS GmbH | Device and method for inductive heating of metal material |
-
1999
- 1999-07-26 JP JP21086899A patent/JP4115634B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2001035645A (en) | 2001-02-09 |
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